{-# LANGUAGE DeriveDataTypeable #-}{- | An Untyped Lambda Calculus AST -}moduleLanguage.Lambda.Untyped.SyntaxwhereimportData.Data-- | A polymorphic version of the AST to allow different symbol typesdataGExpra=Vara|App(GExpra)(GExpra)|Lama(GExpra)deriving(Show,Eq,Data,Typeable)-- | A common symbol type choicetypeSym=String-- | A common ASTtypeExpr=GExprSym